Name

rules — Shorewall6 rules file

Synopsis

/etc/shorewall6/rules

Description

Entries in this file govern connection establishment by defining exceptions to the policies laid out in shorewall6-policy(5). By
default, subsequent requests and responses are automatically allowed using
connection tracking. For any particular (source,dest) pair of zones, the
rules are evaluated in the order in which they appear in this file and the
first terminating match is the one that determines the disposition of the
request. All rules are terminating except LOG and QUEUE rules.

The rules file is divided into sections. Each section is introduced
by a "Section Header" which is a line beginning with ?SECTION and followed
by the section name.

Sections are as follows and must appear in the order listed:

ALL

This section was added in Shorewall 4.4.23. rules in this
section are applied, regardless of the connection tracking state of
the packet.

ESTABLISHED

Packets in the ESTABLISHED state are processed by rules in
this section.

The only ACTIONs allowed in this section are ACCEPT, DROP,
REJECT, LOG and QUEUE

There is an implicit ACCEPT rule inserted at the end of this
section.

RELATED

Packets in the RELATED state are processed by rules in this
section.

The only ACTIONs allowed in this section are ACCEPT, DROP,
REJECT, LOG and QUEUE

There is an implicit rule added at the end of this section
that invokes the RELATED_DISPOSITION (shorewall6.conf(5)).

INVALID

Added in Shorewall 4.5.13. Packets in the INVALID state are
processed by rules in this section.

The only Actions allowed in this section are ACCEPT, DROP,
REJECT, LOG and QUEUE.

There is an implicit rule added at the end of this section
that invokes the INVALID_DISPOSITION (shorewall6.conf(5)).

UNTRACKED

Added in Shorewall 4.5.13. Packets in the UNTRACKED state are
processed by rules in this section.

The only Actions allowed in this section are ACCEPT, DROP,
REJECT, LOG and QUEUE.

There is an implicit rule added at the end of this section
that invokes the UNTRACKED_DISPOSITION (shorewall6.conf(5)).

NEW

Packets in the NEW state are processed by rules in this
section. If the INVALID and/or UNTRACKED sections are empty or not
included, then the packets in the corresponding state(s) are also
processed in this section.

Note

If you are not familiar with Netfilter to the point where you are
comfortable with the differences between the various connection tracking
states, then it is suggested that you omit the ESTABLISHED and RELATED sections and place all of your rules in
the NEW section (That's after the line that reads ?SECTION NEW').

Warning

If you specify FASTACCEPT=Yes in shorewall6.conf(5) then
the ESTABLISHED and RELATED sections must be empty.

An except is made if you are running Shorewall 4.4.27 or later and
you have specified a non-default value for RELATED_DISPOSITION or
RELATED_LOG_LEVEL. In that case, you may have rules in the RELATED
section of this file.

You may omit any section that you don't need. If no Section Headers
appear in the file then all rules are assumed to be in the NEW
section.

The columns in the file are as follows (where the column name is
followed by a different name in parentheses, the different name is used in
the alternate specification syntax).

ACTION - target[:{log-level|none}[!][:tag]]

Specifies the action to be taken if the connection request
matches the rule. target must be one of
the following.

ACCEPT

Allow the connection request.

ACCEPT+

like ACCEPT but also excludes the connection from any
subsequent matching DNAT[-] or REDIRECT[-] rules. Requires Shorewall 4.5.14 or
later.

ACCEPT!

like ACCEPT but exempts the rule from being suppressed
by OPTIMIZE=1 in shorewall6.conf(5).

action

The name of an action declared in
shorewall6-actions(5)
or in /usr/share/shorewall/actions.std.

ADD(ipset:flags)

Added in Shorewall 4.4.12. Causes addresses and/or port
numbers to be added to the named
ipset. The
flags specify the address or tuple
to be added to the set and must match the type of ipset
involved. For example, for an iphash ipset, either the SOURCE
or DESTINATION address can be added using
flagssrc or dst respectively (see the -A command in
ipset (8)).

Beginning with Shorewall 5.0.3, an optional
timeout can be specified. This is
the number of seconds that the new entry in the ipset is to
remain valid and overrides any timeout specified when the
ipset was created.

ADD is non-terminating. Even if a packet matches the
rule, it is passed on to the next rule.

AUDIT[(accept|drop|reject)]

Added in Shorewall 4.5.10. Audits the packet with the
specified type; if the type is omitted, then
drop is assumed. Require AUDIT_TARGET support
in the kernel and iptables.

A_ACCEPT, and A_ACCEPT!

Added in Shorewall 4.4.20. Audited versions of ACCEPT
and ACCEPT! respectively. Require AUDIT_TARGET support in the
kernel and iptables.

A_DROP and A_DROP!

Added in Shorewall 4.4.20. Audited versions of DROP and
DROP! respectively. Require AUDIT_TARGET support in the kernel
and iptables.

A_REJECT AND A_REJECT!

Added in Shorewall 4.4.20. Audited versions of REJECT
and REJECT! respectively. Require AUDIT_TARGET support in the
kernel and iptables.

[?]COMMENT

the rest of the line will be attached as a comment to
the Netfilter rule(s) generated by the following entries. The
comment will appear delimited by "/* ... */" in the output of
"shorewall show <chain>". To stop the comment from being
attached to further rules, simply include COMMENT on a line by
itself.

Note

Beginning with Shorewall 4.5.11, ?COMMENT is a synonym
for COMMENT and is preferred.

CONMARK({mark})

Added in Shorewall 5.0.7, CONNMARK is identical to MARK
with the exception that the mark is assigned to connection to
which the packet belongs is marked rather than to the packet
itself.

CONTINUE

For experts only.

Do not process any of the following rules for this
(source zone,destination zone). If the source and/or
destination IP address falls into a zone defined later in
shorewall6-zones(5)
or in a parent zone of the source or destination zones, then
this connection request will be passed to the rules defined
for that (those) zone(s). See shorewall6-nesting(5)
for additional information.

CONTINUE!

like CONTINUE but exempts the rule from being suppressed
by OPTIMIZE=1 in shorewall6.conf(5).

COUNT

Simply increment the rule's packet and byte count and
pass the packet to the next rule.

DEL(ipset:flags)

Added in Shorewall 4.4.12. Causes an entry to be deleted
from the named ipset. The
flags specify the address or tuple
to be deleted from the set and must match the type of ipset
involved. For example, for an iphash ipset, either the SOURCE
or DESTINATION address can be deleted using
flagssrc or dst respectively (see the -D command in
ipset (8)).

DEL is non-terminating. Even if a packet matches the
rule, it is passed on to the next rule.

DNAT

Forward the request to another system (and optionally
another port). Requires Shorewall 4.5.14 or later.

DNAT-

Advanced users only.

Like DNAT but only
generates the DNAT iptables
rule and not the companion ACCEPT rule. Requires Shorewall 4.5.14
or later.

DROP

Ignore the request.

DROP!

like DROP but exempts the rule from being suppressed by
OPTIMIZE=1 in shorewall6.conf(5).

HELPER

Added in Shorewall 4.5.7. This action requires that the
HELPER column contains the name of the Netfilter helper to be
associated with connections matching this connection. May only
be specified in the NEW section and is useful for being able
to specify a helper when the applicable policy is ACCEPT. No
destination zone should be specified in HELPER rules.

INLINE[(action)]

Added in Shorewall 4.5.16. This action allows you to
construct most of the rule yourself using ip6tables syntax.
The part that you specify must follow a semicolon (';') and is
completely free-form. If the target of the rule (the part
following 'j') is something that Shorewall supports in the
ACTION column, then you may enclose it in parentheses (e.g.,
INLINE(ACCEPT)). Otherwise, you can include it after the
semicolon. In this case, you must declare the target as a
builtin action in shorewall6-actions(5).

Some considerations when using INLINE:

The p, s,
d, i,
o, policy, and state
match (state or conntrack
--ctstate) matches will always appear in the
front of the rule in that order.

When multiple matches are specified, the compiler
will keep them in the order in which they appear
(excluding the above listed ones), but they will not
necessarily be at the end of the generated rule. For
example, if addresses are specified in the SOURCE and/or
DEST columns, their generated matches will appear after
those specified using ';'.

IP6TABLES({ip6tables-target
[option ...])

This action allows you to specify an ip6tables target
with options (e.g., 'IPTABLES(MARK --set-xmark 0x01/0xff)'. If
the ip6tables-target is not one
recognized by Shorewall, the following error message will be
issued:

ERROR: Unknown target (ip6tables-target)

This error message may be eliminated by adding
the
ip6tables-target as a
builtin action in shorewall6-actions(5).

Important

If you specify REJECT as the
ip6tables-target, the target of
the rule will be the i6ptables REJECT target and not
Shorewall's builtin 'reject' chain which is used when REJECT
(see below) is specified as the
target in the ACTION
column.

LOG:level

Simply log the packet and continue with the next
rule.

macro[(macrotarget)]

The name of a macro defined in a file named
macro.macro. If the macro accepts an
action parameter (Look at the macro source to see if it has
PARAM in the TARGET column) then the
macro name is followed by the
parenthesized macrotarget (ACCEPT, DROP, REJECT, ...) to be substituted for the
parameter.

Example: FTP(ACCEPT).

The older syntax where the macro name and the target are
separated by a slash (e.g. FTP/ACCEPT) is still allowed but is
deprecated.

MARK({mark})

where mark is a packet mark
value.

Added in Shorewall 5.0.7, MARK requires "Mark in filter
table" support in your kernel and iptables.

Normally will set the mark value of the current packet.
If preceded by a vertical bar ("|"), the mark value will be
logically ORed with the current mark value to produce a new
mark value. If preceded by an ampersand ("&"), will be
logically ANDed with the current mark value to produce a new
mark value.

Both "|" and "&" require Extended MARK Target
support in your kernel and iptables.

The mark value may be optionally followed by "/" and a
mask value (used to determine those bits of the connection
mark to actually be set). When a mask is specified, the result
of logically ANDing the mark value with the mask must be the
same as the mark value.

The first number specifies the netlink group
(0-65535). If omitted (e.g., NFLOG(,0,10)) then a value of
0 is assumed.

The second number specifies the maximum number of
bytes to copy. If omitted, 0 (no limit) is assumed.

The third number specifies the number of log
messages that should be buffered in the kernel before they
are sent to user space. The default is 1.

NFLOG is similar to
LOG:NFLOG[(nflog-parameters)],
except that the log level is not changed when this ACTION is
used in an action or macro and the invocation of that action
or macro specifies a log level.

NFQUEUE[([queuenumber1[:queuenumber2][,bypass]]|bypass)]

Queues the packet to a user-space application using the
nfnetlink_queue mechanism. If a
queuenumber1 is not specified,
queue zero (0) is assumed. Beginning with Shorewall 4.6.10,
the keyword bypass can be
given. By default, if no userspace program is listening on an
NFQUEUE, then all packets that are to be queued are dropped.
When this option is used, the NFQUEUE rule is silently
bypassed instead. The packet will move on to the next rule.
Also beginning in Shorewall 4.6.10, a second queue number
(queuenumber2) may be specified.
This specifies a range of queues to use. Packets are then
balanced across the given queues. This is useful for multicore
systems: start multiple instances of the userspace program on
queues x, x+1, .. x+n and use "x:x+n". Packets belonging to
the same connection are put into the same nfqueue.

NFQUEUE![([queuenumber1[,queuenumber2][,bypass]]|bypass)]

like NFQUEUE but exempts the rule from being suppressed
by OPTIMIZE=1 in shorewall6.conf(5).

NONAT

Excludes the connection from any subsequent DNAT[-] or REDIRECT[-] rules but doesn't generate
a rule to accept the traffic. Requires Shorewall 4.5.14 or
later.

QUEUE

Queue the packet to a user-space application such as
ftwall (http://p2pwall.sf.net). The application may reinsert
the packet for further processing.

QUEUE!

like QUEUE but exempts the rule from being suppressed by
OPTIMIZE=1 in shorewall6.conf(5).

REDIRECT

Redirect the request to a server running on the
firewall. Requires Shorewall 4.5.14 or later.

REDIRECT-

Advanced users only.

Like REDIRECT but only
generates the REDIRECT
iptables rule and not the companion ACCEPT rule. Requires Shorewall 4.5.14
or later.

REJECT[(option)]

disallow the request and return an icmp-unreachable or
an RST packet. If no option is passed, Shorewall selects the
appropriate option based on the protocol of the packet.

Beginning with Shorewall 5.0.8, the type of reject may
be specified in the option
paramater. Valid option values
are:

icmp6-no-route

no-route

icmp6-adm-prohibited

adm-prohibited

icmp6-addr-unreachable

addr-unreach

icmp6-port-unreachable

tcp-reset (the PROTO column must
specify TCP)

REJECT!

like REJECT but exempts the rule from being suppressed
by OPTIMIZE=1 in shorewall6.conf(5).

TARPIT [(tarpit | honeypot | reset)]

Added in Shorewall 4.6.6.

TARPIT captures and holds incoming TCP connections using
no local per-connection resources.

TARPIT only works with the PROTO column set to tcp (6),
and is totally application agnostic. This module will answer a
TCP request and play along like a listening server, but aside
from sending an ACK or RST, no data is sent. Incoming packets
are ignored and dropped. The attacker will terminate the
session eventually. This module allows the initial packets of
an attack to be captured by other software for inspection. In
most cases this is sufficient to determine the nature of the
attack.

This offers similar functionality to LaBrea
<http://www.hackbusters.net/LaBrea/> but does not
require dedicated hardware or IPs. Any TCP port that you would
normally DROP or REJECT can instead become a tarpit.

The target accepts a single optional parameter:

tarpit

This mode is the default and completes a
connection with the attacker but limits the window size
to 0, thus keeping the attacker waiting long periods of
time. While he is maintaining state of the connection
and trying to continue every 60-240 seconds, we keep
none, so it is very lightweight. Attempts to close the
connection are ignored, forcing the remote side to time
out the connection in 12-24 minutes.

honeypot

This mode completes a connection with the
attacker, but signals a normal window size, so that the
remote side will attempt to send data, often with some
very nasty exploit attempts. We can capture these
packets for decoding and further analysis. The module
does not send any data, so if the remote expects an
application level response, the game is up.

reset

This mode is handy because we can send an inline
RST (reset). It has no other function.

The target may optionally be
followed by ":" and a syslog log level (e.g, REJECT:info or
Web(ACCEPT):debug). This causes the packet to be logged at the
specified level. Note that if the ACTION involves destination network address
translation (DNAT, REDIRECT, etc.) then the packet is logged
before the destination address is
rewritten.

If the ACTION names an
action declared in shorewall-actions(5)
or in /usr/share/shorewall/actions.std then:

If the log level is followed by "!' then all rules in the
action are logged at the log level.

If the log level is not followed by "!" then only those
rules in the action that do not specify logging are logged at
the specified level.

Source hosts to which the rule applies. May be a zone declared
in /etc/shorewall6/zones, $FW to
indicate the firewall itself, all,
all+, all-, all+-
or none.

Beginning with Shorewall 4.4.13, you may use a
zone-list which consists of a
comma-separated list of zones declared in shorewall6-zones (5).
This zone-list may be optionally followed
by "+" to indicate that the rule is to apply to intra-zone traffic
as well as inter-zone traffic.

When none is used either in
the SOURCE or DEST column, the rule is ignored.

all means "All Zones",
including the firewall itself. all-
means "All Zones, except the firewall itself". When all[-] is
used either in the SOURCE or
DEST column intra-zone traffic is
not affected. When all+[-] is "used, intra-zone traffic is affected.
Beginning with Shorewall 4.4.13, exclusion is supported -- see see
shorewall6-exclusion(5).

any is equivalent to
all when there are no nested zones.
When there are nested zones, any
only refers to top-level zones (those with no parent zones). Note
that any excludes all vserver
zones, since those zones are nested within the firewall zone.

Except when all[+][-] or
any[+][-] is
specified, clients may be further restricted to a list of networks
and/or hosts by appending ":" and a comma-separated list of network
and/or host addresses. Hosts may be specified by IP or MAC address;
mac addresses must begin with "~" and must use "-" as a
separator.

Hosts may also be specified as an IP address range using the
syntax
lowaddress-highaddress.
This requires that your kernel and ip6tables contain iprange match
support. If your kernel and ip6tables have ipset match support then
you may give the name of an ipset prefaced by "+". The ipset name
may be optionally followed by a number from 1 to 6 enclosed in
square brackets ([]) to indicate the number of levels of source
bindings to be matched.

Beginning with Shorewall6 4.4.17, the primary IP address of a
firewall interface can be specified by an ampersand ('&')
followed by the logical name of the interface as found in the
INTERFACE column of shorewall6-interfaces
(5).

Beginning with Shorewall 4.5.4, A
countrycode-list may be specified. A
countrycode-list is a comma-separated list of up to 15 two-character
ISO-3661 country codes enclosed in square brackets ('[...]') and
preceded by a caret ('^'). When a single country code is given, the
square brackets may be omitted. A list of country codes supported by
Shorewall may be found at http://www.shorewall.net/ISO-3661.html.
Specifying a countrycode-list requires
GeoIP Match support in your ip6tables and
Kernel.

When an interface is not specified,
you may omit the angled brackets ('<' and '>') around the
address(es) or you may supply them to improve readability.

You may exclude certain hosts from the set already defined
through use of an exclusion (see shorewall6-exclusion(5)).

Subnet 2001:4d48:ad51:24::/64 on the Internet except for
2001:4d48:ad51:24:6:/80.

$FW:&eth0

The primary IP address of eth0 in the firewall zone
(Shorewall6 4.4.17 and later).

Alternatively, clients may be specified by interface by
appending ":" to the zone name followed by the interface name. For
example, loc:eth1 specifies a
client that communicates with the firewall system through eth1. This
may be optionally followed by another colon (":") and an
IP/MAC/subnet address as described above (e.g., loc:eth1:<2002:ce7c::92b4:1::2>).

Examples:

loc:eth1:<2002:cec792b4:1::2,2002:cec792b4:1::44>

Hosts 2002:cec792b4:1::2 and 2002:cec792b4:1::44 in the
Local zone, with both
originating from eth1

Location of Server. May be a zone declared in shorewall6-zones(5),
$FW to indicate the firewall
itself, all. all+ or none.

Beginning with Shorewall 4.4.13, you may use a
zone-list which consists of a
comma-separated list of zones declared in shorewall6-zones (5).
Ths zone-list may be optionally followed
by "+" to indicate that the rule is to apply to intra-zone traffic
as well as inter-zone traffic. Beginning with Shorewall-4.4.13,
exclusion is supported -- see see shorewall6-exclusion(5).

Beginning with Shorewall6 4.4.17, the primary IP address of a
firewall interface can be specified by an ampersand ('&')
followed by the logical name of the interface as found in the
INTERFACE column of shorewall6-interfaces
(5).

Beginning with Shorewall 4.5.4, A
countrycode-list may be specified. A
countrycode-list is a comma-separated list of up to 15 two-character
ISO-3661 country codes enclosed in square brackets ('[...]') and
preceded by a caret ('^'). When a single country code is given, the
square brackets may be omitted. A list of country codes supported by
Shorewall may be found at http://www.shorewall.net/ISO-3661.html.
Specifying a countrycode-list requires
GeoIP Match support in your ip6tables and
Kernel.

When none is used either in
the SOURCE or DEST column, the rule is ignored.

When all is used either in
the SOURCE or DEST column intra-zone traffic is not
affected. When all+ is used,
intra-zone traffic is affected.

If the DEST zone is a bport zone,
then either:

the SOURCE must be all[+][-], or

the SOURCE zone must be
another bport zone associated with the same bridge, or

the SOURCE zone must be an
ipv4 zone that is associated with only the same bridge.

Except when all[+]|[-] is specified, the server may be
further restricted to a particular network, host or interface by
appending ":" and the network, host or interface. See SOURCE above.

You may exclude certain hosts from the set already defined
through use of an exclusion (see shorewall6-exclusion(5)).

Restriction: MAC addresses are not allowed (this is a
Netfilter restriction).

If your kernel and ip6tables have ipset match support then you
may give the name of an ipset prefaced by "+". The ipset name may be
optionally followed by a number from 1 to 6 enclosed in square
brackets ([]) to indicate the number of levels of destination
bindings to be matched. Only one of the SOURCE and DEST columns may specify an ipset
name.

The port that the server is
listening on may be included and separated from the server's IP
address by ":". If omitted, the firewall will not modify the
destination port. A destination port may only be included if the
ACTION is DNAT or REDIRECT.

Example 1:

loc:[2001:470:b:227::44]:3128 specifies
a local server at IP address 2001:470:b:227::44 and listening
on port 3128.

Example 2:

loc:[]:3128 specifies
that the destination port should be changed to 3128 but the IP
address should remain the same.

The port may be specified as a service
name. You may specify a port range in the form
lowport-highport to cause connections to be
assigned to ports in the range in round-robin fashion. When a port
range is specified, lowport and
highport must be given as integers; service
names are not permitted. Additionally, the port range may be
optionally followed by :random
which causes assignment to ports in the list to be random.

If the ACTION is REDIRECT or REDIRECT-, this column needs only to contain
the port number on the firewall that the request should be
redirected to. That is equivalent to specifying
$FW::port.

Optional destination Ports. A comma-separated list of Port
names (from services(5)), port numbers or port ranges; if the
protocol is icmp, this column is
interpreted as the destination icmp-type(s). ICMP types may be
specified as a numeric type, a numeric type and code separated by a
slash (e.g., 3/4), or a typename. See http://www.shorewall.net/configuration_file_basics.htm#ICMP.
Note that prior to Shorewall6 4.4.19, only a single ICMP type may be
listed.

If the protocol is ipp2p,
this column is interpreted as an ipp2p option without the leading
"--" (example bit for bit-torrent).
If no port is given, ipp2p is
assumed.

A port range is expressed as
lowport:highport.

This column is ignored if PROTO = all
but must be entered if any of the following columns are supplied. In
that case, it is suggested that this field contain a dash (-).

If your kernel contains multi-port match support, then only a
single Netfilter rule will be generated in this list and the
SPORT list below if:

1. There are 15 or less ports listed.

2. No port ranges are included or your kernel and ip6tables
contain extended multi-port match support.

Beginning with Shorewall 4.6.0, an
ipset name can be specified in this
column. This is intended to be used with
bitmap:port ipsets.

Beginning with Shorewall 4.5.15, you may place '=' in this
column, provided that the DPORT column is non-empty. This causes the
rule to match when either the source port or the destination port in
a packet matches one of the ports specified in DPORT. Use of '='
requires multi-port match in your iptables and kernel.

Warning

Unless you really understand IP, you should leave this
column empty or place a dash (-)
in the column. Most people who try to use this column get it
wrong.

If you don't want to restrict client ports but need to specify
a later column, then place "-" in this column.

If your kernel contains multi-port match support, then only a
single Netfilter rule will be generated if in this list and the
DPORT list above:

1. There are 15 or less ports listed.

2. No port ranges are included or your kernel and ip6tables
contain extended multi-port match support.

Beginning with Shorewall 4.6.0, an ipset name can be specified
in this column. This is intended to be used with
bitmap:port ipsets.

This column was formerly labelled SOURCE PORT(S).

ORIGDEST - [-]

Included for compatibility with Shorewall. Enter '-' in this
column if you need to specify one of the later columns.

You may optionally rate-limit the rule by placing a value in
this column:

rate* is the number of connections per
interval (sec or min) and burst* is the
largest burst permitted. If no burst is given,
a value of 5 is assumed. There may be no no white-space embedded in
the specification.

Example: 10/sec:20

When s: or d: is specified,
the rate applies per source IP address or per destination IP address
respectively. The names may be chosen by
the user and specify a hash table to be used to count matching
connections. If not given, the name shorewallN (where N is a unique integer) is
assumed. Where more than one rule or POLICY specifies the same name,
the connections counts for the rules are aggregated and the
individual rates apply to the aggregated count.

Beginning with Shorewall 4.6.5, two
limits may be specified, separated by a comma. In this
case, the first limit (name1,
rate1, burst1) specifies the per-source
IP limit and the second limit specifies the per-destination IP
limit.

Example: client:10/sec:20,:60/sec:100

In this example, the 'client' hash table will be used to
enforce the per-source limit and the compiler will pick a unique
name for the hash table that tracks the per-destination
limit.

This optional column may only be non-empty if the SOURCE is
the firewall itself.

When this column is non-empty, the rule applies only if the
program generating the output is running under the effective
user and/or group
specified (or is NOT running under that id if "!" is given).

Beginning with Shorewall 4.5.8, multiple user or group
names/ids separated by commas may be specified.

Examples:

joe

program must be run by joe

:kids

program must be run by a member of the 'kids'
group

!:kids

program must not be run by a member of the 'kids'
group

2001-2099

UIDs 2001 through 2099 (Shorewall 4.5.6 and
later)

This column was formerly labelled USER/GROUP.

MARK - [!]value[/mask][:C]

Defines a test on the existing packet or connection mark. The
rule will match only if the test returns true.

If you don't want to define a test but need to specify
anything in the following columns, place a "-" in this field.

!

Inverts the test (not equal)

value

Value of the packet or connection mark.

mask

A mask to be applied to the mark before testing.

:C

Designates a connection mark. If omitted, the packet
mark's value is tested.

CONNLIMIT - [d:][!]limit[:mask]

May be used to limit the number of simultaneous connections
to/from each individual host or network to
limit connections. Requires connlimit
match in your kernel and iptables. While the limit is only checked
on rules specifying CONNLIMIT, the number of current connections is
calculated over all current connections from the SOURCE or
DESTINATION host. By default, limiting is done by SOURCE host or
net, but if the specification begins with d:, then limiting will be donw by destination
host or net.

By default, the limit is applied to each host but can be made
to apply to networks of hosts by specifying a
mask. The mask
specifies the width of a VLSM mask to be applied to the source
address; the number of current connections is then taken over all
hosts in the subnet
source-address/mask.
When ! is specified, the rule matches when the
number of connection exceeds the
limit.

TIME -
timeelement[&timeelement...]

May be used to limit the rule to a particular time period each
day, to particular days of the week or month, or to a range defined
by dates and times. Requires time match support in your kernel and
ip6tables.

timeelement may be:

timestart=hh:mm[:ss]

Defines the starting time of day.

timestop=hh:mm[:ss]

Defines the ending time of day.

contiguous

Added in Shoreawll 5.0.12. When timestop is smaller than timestart value, match this as a single
time period instead of distinct intervals.

utc

Times are expressed in Greenwich Mean Time.

localtz

Deprecated by the Netfilter team in favor of kerneltz. Times are expressed in Local
Civil Time (default).

kerneltz

Added in Shorewall 4.5.2. Times are expressed in Local
Kernel Time (requires iptables 1.4.12 or later).

The header-list consists of a
comma-separated list of headers from the following list.

auth, ah, or 51

Authentication Headers extension
header.

esp, or 50

Encrypted Security Payload
extension header.

hop, hop-by-hop or 0

Hop-by-hop options extension header.

route, ipv6-route or 43

IPv6 Route extension header.

frag, ipv6-frag or 44

IPv6 fragmentation extension header.

none, ipv6-nonxt or 59

No next header

proto, protocol or 255

Any protocol header.

If any: is specified, the
rule will match if any of the listed headers are present. If
exactly: is specified, the will
match packets that exactly include all specified headers. If neither
is given, any: is assumed.

If ! is entered, the rule
will match those packets which would not be matched when ! is omitted.

SWITCH -
[!]switch-name[={0|1}]

Added in Shorewall6 4.4.24 and allows enabling and disabling
the rule without requiring shorewall6
restart.

Enables the rule if the value stored in
/proc/net/nf_condition/switch-name
is 1. Disables the rule if that file contains 0 (the default). If
'!' is supplied, the test is inverted such that the rule is enabled
if the file contains 0.

Within the switch-name, '@0' and
'@{0}' are replaced by the name of the chain to which the rule is a
added. The switch-name (after '@...'
expansion) must begin with a letter and be composed of letters,
decimal digits, underscores or hyphens. Switch names must be 30
characters or less in length.

Switches are normally off. To
turn a switch on:

echo 1 >
/proc/net/nf_condition/switch-name

To turn it off again:

echo 0 >
/proc/net/nf_condition/switch-name

Switch settings are retained over shorewall6
restart.

Beginning with Shorewall 4.5.10, when the
switch-name is followed by
=0 or =1, then the switch is
initialized to off or on respectively by the
start command. Other commands do not affect the
switch setting.

HELPER - [helper]

Added in Shorewall 4.5.7.

In the NEW section, causes the named conntrack
helper to be associated with this
connection; the contents of this column are ignored unless ACTION is
ACCEPT*, DNAT* or REDIRECT*.

In the RELATED section, will only match if the related
connection has the named helper
associated with it.

The helper may be one of:

amanda

ftp

irc

netbios-ns

pptp

Q.931

RAS

sane

sip

snmp

tftp

If the HELPERS option is specified in shorewall6.conf(5),
then any module specified in this column must be listed in the
HELPERS setting.